The endsperm of a plant is haploid, diploid or triploid.

Explanation

To determine whether the endosperm of a plant is haploid, diploid, or triploid, we can follow these steps:

### Step 1: Understand the concept of endosperm
The endosperm is a tissue in seed plants that provides nutrition to the developing embryo. It is formed during the fertilization process in flowering plants (angiosperms).

**Hint:** Look into the role of endosperm in seed development.

### Step 2: Learn about double fertilization
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